code: def setUp(self):
      self.x = chainer.Variable(
          numpy.random.uniform(-1, 1, self.x_shape).astype(
              numpy.float32
          )
      )
  
file_path: chainer/tests/chainer_tests/functions_tests/activation_tests/test_maxout.py
imports: import unittest
  import numpy
  import chainer
  from chainer import functions
  from chainer import testing
  from chainer.testing import attr
  from chainer.utils import type_check
label_desc: Use image node_id 1 for calling the InvalidArgument obj's underlying member method code with example usage: obj.setUp() without return types